I see what Fred is saying. If this is not done right, the bushing becomes a sort of torsion bar that is adding extra spring to the suspension (or taking it away). Not sure how much that really is compared to the coilover spring itself. But this car is all about the handling, so why not make sure this part is right? Would it help to replace this bushing with a free-floating one, like a polyurathane? Something that could be lubed up and would not provide any 'sprung' resistance?